PPRuNe Forums - View Single Post - Indonesian aircraft missing off Jakarta
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29th Oct 2018, 19:54

Join Date: Jan 2018
Location: London
Posts: 4
Originally Posted by A Squared
Yeah, we're not discussing an airplane whcih was flying in conditions where a 300 knot groundspeed and an EAS of 100 knots are simultaneously possible. We're discussing the Indonesian 737 which crashed a day ago. That airplane was no higher than about 5000 ft MSL Neglecting winds, a 300 knot groundspeed equates to about 275 knot IAS at that altitude. Winds in excess of 20-30 knots at 5000 ft are unlikely unless there was some fairly unusual weather going on. I haven't heard any mention of extraordinarily strong winds in this accident, have you? No? So if we assume a tailwind at the upper end of that range, we're still probably looking at an IAS greater than 245 knots, if an airplane at 5000 ft is showing a groundspeed of 300 knots.

In order to get a 300 knot groundspeed with an EAS of 100 knots you'd have to be somewhere around 40,000 ft with a 100 knot tailwind. Were you under the impression that this airplane in this accident that we're discussing here, today, in this thread, was at 40,000 ft, with a 100 knot tailwind? No? If not, what on earth is your point in even mentioning that? What relevance do you imagine that brings to this discussion?
Sorry, I'm with A squared on this one. You guys barking on about the fact that it's theoretically possible there is a 200 knot difference between groundspeed and TAS at 5,000ft on departure into calm whether are keyboard warrior idiots, frankly.

As to the guy with the "NOT theoretical, actual" - NO. Theoretical. In this context that means "pretty unlikely but possible in theory". And that's exactly what it is. To say something is "actually" possible or "literally" possible is no different from saying it's theoretically possible. Theoretically possible doesn't mean it's NOT possible, it means it's possible. In theory. But most likely not in practice in the circumstances in which the plane found itself.

Honestly, I pray to god I never have to fly with argumentative morons like the pair of you. A squared has been pretty restrained.